Gilead Sciences, Inc. announced that Japan’s Ministry of Health, Labour and Welfare (MHLW) has approved Epclusa® (sofosbuvir 400mg/velpatasvir 100mg), a once-daily treatment for adults with chronic hepatitis C virus (HCV) infection with decompensated cirrhosis, and for patients with chronic HCV infection without cirrhosis or with compensated cirrhosis who have had prior treatment with a direct-acting antiviral therapy (DAA). Until now, no treatment option has been available in Japan for the treatment of chronic HCV infection with decompensated cirrhosis, and there have been limited treatment options for patients with chronic HCV infection who have had prior treatment with a DAA. Epclusa offers a new option for both of these difficult-to-treat patient populations. Epclusa is a combination treatment that contains sofosbuvir, an NS5B polymerase inhibitor that was approved in Japan as Sovaldi® 400 mg tablets in March 2015, and velpatasvir, an active ingredient that inhibits NS5A. In Japan, Epclusa is indicated for the suppression of viremia in patients with chronic HCV infection. Patients with chronic HCV infection with decompensated cirrhosis should take one tablet of Epclusa once daily for 12 weeks, and patients with chronic HCV infection without cirrhosis or with compensated cirrhosis that have had prior DAA treatment experience should take one tablet of Epclusa once daily for 24 weeks, in combination with ribavirin (RBV). The approval of Epclusa in Japan is supported by data from a Phase 3 clinical study in Japanese patients with HCV infection with decompensated cirrhosis (Study GS-US-342-4019) in which 92% (47/51) of patients who received Epclusa for 12 weeks achieved SVR12 (defined as undetectable HCV RNA 12 weeks after completing therapy). Patients who achieve SVR12 are considered cured of HCV. In a separate Phase 3 clinical study in Japanese patients with genotype 1 or 2 HCV infection who failed prior DAA therapy (Study GS-US-342-3921), 97% (58/60) of patients who received Epclusa with RBV for 24 weeks achieved SVR12. In both studies, Epclusa was generally well tolerated. Among patients receiving Epclusa for 12 weeks in GS-US-342-4019, the most common adverse event was nasopharyngitis and no patient discontinued treatment with Epclusa due to adverse events. Among patients receiving Epclusa with RBV for 24 weeks in GS-US-342-3921, the most common adverse events were viral upper respiratory tract infection and anemia and 3.3% of patients discontinued Epclusa due to adverse events.